WASHINGTON (JTA) — Bernie Sanders, the independent senator from Vermont and the only self-described socialist in Congress, has long been an outspoken voice in Washington on issues of economic inequality.

But with the vanishing middle class figuring prominently in the campaign for mayor of the country’s largest city, and President Obama last month calling the gap between rich and poor “the defining issue of our time,” Sanders’ pet political cause has moved to the forefront of the national discussion.

“There has been an understanding in the Democratic Party that now is the time to focus on protecting the collapsing middle class and the needs of moderate- to low-income Americans,” Sanders told JTA in an interview. “When the middle class is shrinking and the wealthiest people are doing phenomenally well, we do need revenue to come from the wealthiest people in the country.”

Sanders, 72, who has long caucused with the Democrats, is one of 10 Jewish members in the U.S. Senate. The native of Brooklyn, N.Y., is the son of Polish immigrants whose father’s family was wiped out in the Holocaust, according to a 2007 New York Times profile.

After graduating from the University of Chicago, Sanders spent time on an Israeli kibbutz around 1963 — notably before the 1967 Six-Day War, when it was not common for American youngsters to spend time in Israel.

But Sanders is hesitant to draw a connection between his Jewish background and his priorities as a senator. With a series of observations about the Jewish history of rootlessness and oppression, Sanders begins to describe the role of his lower-middle-class upbringing in forging him into the Congress’ only self-described socialist. Then he catches himself.

“This isn’t a profile,” he declared, interrupting himself. “There are very important issues that need to be discussed — the collapse of the middle class, very high unemployment rates, the crisis of climate change, the widening income gap.”

With a bespectacled face framed by a wild mop of white hair and a lingering tendency to bark in Brooklyn intonations even after 45 years in Vermont, Sanders is one of the more identifiably Jewish senators.

“As everyone in this room knows, I am a Jew, an old Jew,” the actor Fred Armisen, portraying Sanders, announced in an unaired “Saturday Night Live” sketch last year to knowing guffaws from the other members of the Senate Armed Services Committee.

Now with income inequality becoming a defining issue in the 2014 midterm elections, Sanders is gaining a different kind of attention. He has become a go-to talking head on the subject on cable news networks, including the conservative Fox News.

“You have the Walton family of Walmart owning more wealth than the bottom 40 percent,” Sanders said. “While at the same time we’ve had a huge growth in the number of millionaires and billionaires.”

Sanders’ focus on issues of income inequality are true to his socialist reputation — one he continues to embrace as fiercely as he did in 1980, when he was the surprise winner of a mayoral election in Burlington, Vt. In 1990, he was elected to the U.S. House of Representatives, and in 2006 won his first Senate election.

Sanders acknowledges a certain stigma attached to the label socialist, but believes Americans would be likelier to embrace the term if they were better informed about the benefits of socialism.

“The ideas do resonate, but there is a stigma regarding the word,” he said. “We went through a McCarthyite period, a Cold War with the Soviet Union. There is a misperception of what democratic socialism is.”

That might be changing. Where Sanders once was prone to excoriate fellow Democrats for their solicitousness of corporate interests or their failure to oppose cuts to entitlement programs, he now is likelier to praise them for embracing the battles he has waged for years.

Sanders notes Bill de Blasio’s successful run for New York mayor on a platform focused in large part on income inequality. Congress, too, has come along, he says. Entitlement reform formerly was a watchword among Republicans, and even among the president and some Democrats.

Now, Sanders says, “Most Democrats understand that Americans don’t want cuts in Social Security and Medicaid and Medicare. The Democratic Party is becoming more vigorous in trying to extend unemployment benefits, in raising the minimum wage. I see that as a step forward in understanding that the American people do not want to see more attacks on the children, the elderly and the poor.”

There has been speculation that Sanders may run for president as a means of keeping Democrats on the true path. He won’t count it out, but insists, again, that his personal ambitions are not the point — income inequality is.

“I don’t wake up every morning thinking about whether I should be president of the United States,” Sanders said. “But those issues have to be discussed. And if nobody else is, I will discuss them.”